Zernike矩的圆阵列靶标特征点精确提取方法

Extracting Method for Circular Array Target Feature Points of Zernike

以用于视觉测量中摄像机标定的圆阵列靶标特征点提取为研究对象,提出一种像素级粗定位和亚像素边缘检测精确定位相结合的类椭圆轮廓提取算法,进行圆阵列靶标特征点的精确提取。具体方法是首先对圆阵列靶标采用Canny算子提取椭圆像素级边缘,然后应用Zernike矩(模板系数)进行亚像素级的边缘定位,采用最小二乘椭圆拟合法精确求取类椭圆中心点,从而实现圆阵列靶标标定特征点的精确定位。

An elliptical contour extraction is proposed to accurately extract the feature points of circular array target in camera calibration,which combining with the coarse location at pixel level and precise location at sub-pixel level. Firstly,the elliptical contour of circular array target at pixel level is extracted with Canny operator,then Zernike moment（ template coefficient） is used to relocate elliptical contour of circular array target at sub-pixel level. Finally,the least squares ellipse fitting method is applied to accurately calculate the elliptical center and to realize quickly and accurately the position of circular array target calibration feature points.